tools/llvm-mc/AsmParser.h

//===- AsmParser.h - Parser for Assembly Files ------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This class declares the parser for assembly files.
//
//===----------------------------------------------------------------------===//

#ifndef ASMPARSER_H
#define ASMPARSER_H

#include <vector>
#include "AsmLexer.h"
#include "AsmCond.h"
#include "llvm/MC/MCAsmParser.h"
#include "llvm/MC/MCStreamer.h"

namespace llvm {
class AsmExpr;
class AsmCond;
class MCContext;
class MCInst;
class MCStreamer;
class MCValue;
class TargetAsmParser;
class Twine;

class AsmParser : public MCAsmParser {
private:  
  AsmLexer Lexer;
  MCContext &Ctx;
  MCStreamer &Out;
  TargetAsmParser *TargetParser;

  AsmCond TheCondState;
  std::vector<AsmCond> TheCondStack;

public:
  AsmParser(SourceMgr &_SM, MCContext &_Ctx, MCStreamer &_Out)
    : Lexer(_SM), Ctx(_Ctx), Out(_Out), TargetParser(0) {}
  ~AsmParser() {}

  bool Run();
  
public:
  TargetAsmParser &getTargetParser() const { return *TargetParser; }
  void setTargetParser(TargetAsmParser &P) { TargetParser = &P; }

  /// @name MCAsmParser Interface
  /// {

  virtual MCAsmLexer &getLexer() { return Lexer; }

  virtual void Warning(SMLoc L, const Twine &Meg);

  virtual bool Error(SMLoc L, const Twine &Msg);

  virtual bool ParseExpression(AsmExpr *&Res);

  virtual bool ParseAbsoluteExpression(int64_t &Res);

  virtual bool ParseRelocatableExpression(MCValue &Res);

  /// }

private:
  MCSymbol *CreateSymbol(StringRef Name);

  bool ParseStatement();

  bool TokError(const char *Msg);
  
  bool ParseConditionalAssemblyDirectives(StringRef Directive,
                                          SMLoc DirectiveLoc);
  void EatToEndOfStatement();
  
  bool ParseAssignment(const StringRef &Name, bool IsDotSet);

  /// ParseParenRelocatableExpression - Parse an expression which must be
  /// relocatable, assuming that an initial '(' has already been consumed.
  ///
  /// @param Res - The relocatable expression value. The result is undefined on
  /// error.  
  /// @result - False on success.
  ///
  /// @see ParseRelocatableExpression, ParseParenExpr.
  bool ParseParenRelocatableExpression(MCValue &Res);

  bool ParsePrimaryExpr(AsmExpr *&Res);
  bool ParseBinOpRHS(unsigned Precedence, AsmExpr *&Res);
  bool ParseParenExpr(AsmExpr *&Res);

  /// ParseIdentifier - Parse an identifier or string (as a quoted identifier)
  /// and set \arg Res to the identifier contents.
  bool ParseIdentifier(StringRef &Res);
  
  // Directive Parsing.
  bool ParseDirectiveDarwinSection(); // Darwin specific ".section".
  bool ParseDirectiveSectionSwitch(const char *Segment, const char *Section,
                                   unsigned TAA = 0, unsigned ImplicitAlign = 0,
                                   unsigned StubSize = 0);
  bool ParseDirectiveAscii(bool ZeroTerminated); // ".ascii", ".asciiz"
  bool ParseDirectiveValue(unsigned Size); // ".byte", ".long", ...
  bool ParseDirectiveFill(); // ".fill"
  bool ParseDirectiveSpace(); // ".space"
  bool ParseDirectiveSet(); // ".set"
  bool ParseDirectiveOrg(); // ".org"
  // ".align{,32}", ".p2align{,w,l}"
  bool ParseDirectiveAlign(bool IsPow2, unsigned ValueSize);

  /// ParseDirectiveSymbolAttribute - Parse a directive like ".globl" which
  /// accepts a single symbol (which should be a label or an external).
  bool ParseDirectiveSymbolAttribute(MCStreamer::SymbolAttr Attr);
  bool ParseDirectiveDarwinSymbolDesc(); // Darwin specific ".desc"
  bool ParseDirectiveDarwinLsym(); // Darwin specific ".lsym"

  bool ParseDirectiveComm(bool IsLocal); // ".comm" and ".lcomm"
  bool ParseDirectiveDarwinZerofill(); // Darwin specific ".zerofill"

  // Darwin specific ".subsections_via_symbols"
  bool ParseDirectiveDarwinSubsectionsViaSymbols();
  // Darwin specific .dump and .load
  bool ParseDirectiveDarwinDumpOrLoad(SMLoc IDLoc, bool IsDump);

  bool ParseDirectiveAbort(); // ".abort"
  bool ParseDirectiveInclude(); // ".include"

  bool ParseDirectiveIf(SMLoc DirectiveLoc); // ".if"
  bool ParseDirectiveElseIf(SMLoc DirectiveLoc); // ".elseif"
  bool ParseDirectiveElse(SMLoc DirectiveLoc); // ".else"
  bool ParseDirectiveEndIf(SMLoc DirectiveLoc); // .endif

  bool ParseDirectiveFile(SMLoc DirectiveLoc); // ".file"
  bool ParseDirectiveLine(SMLoc DirectiveLoc); // ".line"
  bool ParseDirectiveLoc(SMLoc DirectiveLoc); // ".loc"

  /// ParseEscapedString - Parse the current token as a string which may include
  /// escaped characters and return the string contents.
  bool ParseEscapedString(std::string &Data);
};

} // end namespace llvm

#endif